Process for treating organic substitution derivative of cellulose textile materials



Patented Nov. 22, 1949 UNITED STATES PATENT orrlce TUTI N D RIVATIVE TILE MATERIALS 7 OF CELLULOSE TEX- Camille Dreyfus'New York. N. Y., and George W. Seymour and-George C. Ward, Cumberland, Md., assignors to Celanese Corporation of America, a corporation of Delaware No Drawing. Application June 7, 1945,

8 Serial N0. 598,204

7 Claims. (01. 117-65) This invention relates to the treatment of fab.- rics and relates more particularlyv to the treatment of fabrics made of or containing yarns having. a basis of cellulose acetate or other organic derivative of cellulose whereby the heat resistance and ironing qualities of said fabrics may be improved.

An object of this invention is the provision of an improved process for the treatment of fabrics made of or containing cellulose acetate or other organic derivative of cellulose yarns whereby the safe ironing temperature thereof may be raised effectively and the hand, draping qualities and other characteristics of the fabrics may be improved.

Another object of this invention is to provide a process for raising the safe ironing temperature of fabrics made of or containing cellulose acetate or other organic derivativeofcellulose yarns whereby the improvement efiected is substantially permanent and resistant to the action of dry cleaning agents, and the like.

Other objects of this invention will appear from the following detailed description.

Cellulose acetate or other organic derivative of cellulose materials employed for the commercial production of filaments, yarns, threads and the like are thermoplastic. Therefore, exposure of these materials for even a relatively short time;

to elevated temperatures on the order of 230 C. or higher will effect a pronounced physical change therein. If exposed to temperatures above the softening point for longer periods of time, the cellulose acetate filaments will not only soften but their filamentary character will ultimately be destroyed. For example, fabrics containing cellulose acetate or other organic derivative of cellulose yarns or filaments ironed at too high a temperature become glossy and stiff due to a softening or melting of the surface filments, and assume a wholly undesirable appearance. 7

We have now discovered that the ironing characteristics of textile materials made of or containing yarns of filaments having a basis of cellulose acetate or other thermoplastic organic 'derivative of cellulose may be greatly improved by subjecting them to treatment with an aqueous solution of boric'acid and then subjecting the so treated fabric to a heat treament. The treatment of the textile material with the boric acid solu tion may be effected by padding with, or dip-ping or rinsing in an aqueous solution, preferably containing 1 to by weigh of boric acid. The heat treatment to which the textile material is then. subjected may involve hot calenderingor mangling or decatizing. This treatment empioy: ing elevated temperatures eliminates the tendency 2 a v of a hot hand iron to stick to the fabric during an ironing operation and greatly improves the hand. Thetemperatures to which the treated fabric may then be safely exposed during ironing without any lustering, stiifening or the like taking place, isfound to be substantially higher than in the case of untreated fabrics.

When a padding operation is used, the aqueous solution of boric acid is preferably applied to the fabric by causing the fabric to pass. through the boric acid solution and then through a pair of nip rollers, the clearancecbetween said rollers being adjusted so thatthe fabric retains from '75 to 125% by weight of the solution. The treated fabric is then dried in a suitable chamber through whichheated air at a temperature of 85 110 100" C, is circulated.

After drying, the hand of the treated fabric is somewhat harsher than originally. This, as well as the tendency of the hand iron to stick, may be 8000 pounds per square inch entrely eliminated by hot calendering 0r mangling or decatizing. When subjecting the treated fabricto mangling or hot calendering, temperatures of; 110 to 150 C.;and pressures 0152000 to are. usually employed. I, The decatizing treatmentemployed may consist in winding the fabric onto a perforated metal drum with a heavy cotton blanket'or apron so that alayer of the cotton blanket or apron alternates with each layer of the fabric, Steam at a pressure of the order of 10 pounds per square inch or more is then passed through the fabric for 3 to 5 minutes, whereby the temperature of the fabric is raised to to 0., thereupon the steam is shut off and vacuum is applied to cool the fabric and remove any condensed water present'. r

The cellulose acetate or other organic derivative of cellulose fabric obtained after treatment in accordance with our novel'process may then be dry-cleaned and the improved properties of the fabric are wholly retained without being in originalproperties observed prior to treatment.

In order further to illustrate our invention but without being limited thereto, the following examples are given:

Example I A cellulose acetate fabric of taffeta weave is padded with a 15% aqueous solution of boric acid at" 85 -C.,--the fabric being' permitted to retain about 100% by weight of the solution. The padded fabric is then dried with air heated to 100 C. in a suitable drying chamber. The fabric obtained is entirely unaffected by ironing with a hand iron ata temperature of 220 C. butthe iron exhibits a pronounced tendency to stick thereto. This may be entirely eliminated by our physical appearance of the fabric alternate-* Fabric to which no boric acid has-been applied a and given the stroke ironing test withthe= iron at 220 C. undergoes a considerable degree of physical change due to a softening or memes of the cellulose acetate filaments.

Example II V A cellulose acetate tricot fabric is' padded with a=-5%v aqueous solutionof' boric acid 'at 38 CQ, the fabric'bei'ng permitted t'o '"retz'a.'in about 100% by weig'htmf the"'solution; The paddedfabri'c is dried in a suitable"=di y-ing chamber- 'with air heate'd -to llo C: The'dried' fabric is decatized at 95 m 110 C. 1 The treatment comprises wind: ing the -fa'bric on a perforated m'etal drum"to"- geth'er" witlia cotton apron so that the 'cotto'ri apron-"lies between each" layer of the} fabric aridpassing steam at 10 pounds per square inch pre surethrough the"'fabric for 5 "r 'nii'iute's'. The flowmf stea'm is the'n halted' enu ve-cuumis 'a'p plieii to cool the" f abric' amr remove cori densed water. The treated fabric is entirely" unarfected byiallowing'a hand ir'onat 250 C. tor'est thereon a stationary" ositio'ri rcr ioseconds; Untreatedf abric becomes stiffeneu" aritlia'zee under the' '10 "second-"stationary"iron test at 250C'L With theirori' at 270 C1, the"ti'eated fabric" becomesonly slightly stl'fin'd while ill-ii treated fabric undergoes-such a degree of i change during tlie-10"second test piiod as to glaie and 4a stick to the heated surface of the iron.

Other'methods' of applying 'the borijc 'acid s'olutionsmay' be used-'5 Thus garments made of fabrics comprisiiig' 'oiganic i derivative of cellulose yarn after they afe laundered either at' horheorl in 3 commercial laundiies' may 1 be" given a "final fit'i's'e in 'theboric acidsolution and then subjected 'to hydro-extracting or vacuum extracti'ng' and then mangled. Thereupon, the garments in'e'y fie-ironed with areasonably*hot irbnwithout danger or causing stiffening or glazing.

irripc'rtaiit -use-erthis invention is inco"nnection with the treatment of fabrics made ofo'r' containing c'r'gaziiefderrvauve of cellulose fibres that are used forthe manufacture of 'mens or woirieris suitsor' coats'. During the manufacture of s'uch'garments',-the fabrics are'subjeted to manys'mo'othing' operations" usually bymeans of Hofimann presses oro'ther presses wherein steam is passed through the fabric. Also afterthese garments are'm'ade, they are pressed bybuch presses bothby" the manufacturer and bytailors and'dry clean'ers. When outer'fabrics made-of or containing cellulose acetate fniaterial'whether in the formof "continuous filaments or staple fibers and/ or linings made of such cellulose a'cetate material are used;' dften glazing of the material-resultsr However; if suchfabricsor-garmerits-made of=such-fabric-are treated in--ac-; cordance with-- this invention; the ironing pointis raised sufficiently high to permit the safe use of such presses.

While our invention has been more particularly described inconnectionwith the treatment of fabrics having a'basis of yarns of cellulose acetate, it is to be understood that equally desirable results are obtained when treating fabrics having a basis of other organic derivatives of "eellulos'e. mars es 'of other organic derivatives of eentib'seere cellulose esters, such as cellulose ro'pieriete, cellulose butyrate, cellulose acetatepropionate -and-cellulose acetate-butyrate or cellulose ethers such' as ethyl cellulose or benzyl *ce'llul'oser The "expression" organic substitution derivative of cellulose as employed in the claims is tciabe construed as including within its scope onl cellulose ethers and cellulose esters of fatty acids? It is to be understood that the foregoing detailed description is givenmerelybyway ofillustranscend that many variations may be made therein without departing from the 'spirit of ouriziventiorr.

Having described ourinvention wh'at' we desire to seciire by 'Letters- Patent is 1'.' 'Pro'eess fo'rimproving'the ironingaproperties of 'or ganic substitution derivative of'cellulose textfle rnaterialsand articles made therefrom, which comprises'treating the same with an aqueous solutib'ri of =boric acid; drying the material, and then ectin'g th'e 50 treated material to'a heat treatifint 'at a temperaturebf atleast C. under a pressure of at least 2000 pounds per square inch? *2. Process fori'mp'foving the ironing properties csceueiose acetate textile materials and articles niade -therefremgwhichcomprises treating the sal ne 'witli an aqueous solution of boric'acid, dryiiig' the 'mate'rial; and then subjecting the so treated material to a' heat treatment at atempratiii'e ofat least-110 C. under a pressure of at least 2000 pounds per square inch.

syrreeess for irnprovmg' the ironing propertiesbfdr'ganicsubstitution derivative of cellulose t'itile---rn'aterials and articles m'ade therefrom, which comprises treating the"sarne' with a 1' to 15% ajueous solfitio'n of boric acid, drying the material, and then subjecting the so treated material to a-heat treatment ata temperature of at least-110 C. under a-pressure of at least 2000 pounds per square inch.

4.Process for improving the ironing properties of cellulose acetate textile materials and articles made therefrom, which comprises treatingthe'samewith al to 15% aqueoussolution of beric acidfdry'ihghe material, and then subjecting the-so treated material to a heat treatme'nt'at a temperature of at least110 C. under a pressure of at least 2000 pounds per square inch.

5; Process forim'proving the ironing properties jof organic substitution derivative of cellulose textile materials, which comprises applying an aqueous solution of boric acid to said organic derivative of cellulose textile materials, drying thema'terialsand subjecting the materials to ahat treatment at a'temperature of 1 10 to Clu'nder a pressure of' at least 2000'pou'n'ds-per square inch whereby the safe ironing temperature 6f the textile materials is substantially raised and theironing qualities improved.

, 6.- Process-for-improving the ironingproperties of cellulose acetate textile materials, which comprises-applying anaqueoussolution of boric acid to saidcellulose acetate textile materials, drying the materials, and subjecting the materials to a heat treatment at a temperature of 110 to 150 C. under a pressure of at least 2000 pounds per square inch whereby the safe ironing temperature of the textile materials is substantially raised and the ironing qualities improved.

7. Process for improving the ironing properties of cellulose acetate textile materials, which comprises applying a 1 to 15% aqueous solution of boric acid to said cellulose acetate textile materials, drying the materials, and subjecting the materials to hot calendering at a temperature of 110 to 130 C. under a pressure of between 2000 to 8000 pounds per square inch whereby the safe ironing temperature of the textile materials is substantially raised and the ironing qualities improved.

CAMILLE DREYFUS. GEORGE W. SEYMOUR. GEORGE C. WARD.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 

